Nanotechnology and nanosensors in smell sense imitation
Nanotechnology and nanosensors in smell sense imitation
Students:
Sabina Wilkanowicz Sankaranarayanan L. Marco Antonio Balbino
Course instructor:
Prof. Hossam Haick
Nanotechnology and Nanosensors by Coursera and TECHNION, Israel Institute of Technology 2015
Actually, I am a Project Leader at Bioinicia S.L., where I’m responsible for projects related to encapsulation of sensitive bioactive compounds using electro-hydrodynamic processing. I have a PhD in Chemical Sciences in the field of Biotechnology. My PhD research conducted at the Department of Microbiology, Gdansk University of Technology, Poland, was associated with the analysis of biofilm formation by uropathogenic E. coli strains. During PhD studies I had worked at Microbial Ecology, Nutrition and Health Department and Novel Materials and Nanotechnology Department at IATA-CSIC (Spain), where I started to work in a new research line related to influence of probiotics on human health and encapsulation of probiotics by electro-hydrodynamic processing. After my PhD thesis I also worked at EURx Molecular Biology Products (Poland) as a R&D Project Leader, where I was responsible for cloning, overexpressing and purification of new recombinant enzymes (restriction enzymes, polymerases, reverse transcriptase) and creation of new kits to purification of DNA and RNA, used in molecular biology. I have more than 10 years of experience and practical knowledge about chemical engineering, molecular biology, genetics, chemistry and microbiology.
Table of contents: 1. ABSTRACT ............................................................................................................................... 3 2. INTRODUCTION ...................................................................................................................... 3 3. SMELL NANOSENSORS – LITERATURE REVIEW ............................................................. 4 4. OVERALL DESIGN OF NEW THEORETICAL SMELL NANOSENSOR ............................ 5 6. POSSIBLE APPLICATIONS OF NEW GENERATION SMELL NANOSENSORS ............... 7 7. CONCLUSIONS ........................................................................................................................ 8 8. REFERENCES ........................................................................................................................... 8
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1. Abstract New technologies allow us to create new, better sensors, which can help people with disabilities sense or feel as healthy ones. Nanotechnology and nanosensors can be a great opportunity for us in the future to live better and easier. Creation of new electronic olfactory nanosensors can allow people to smell as sensible as other mammalians, like dogs for example. This great idea can help us to live easier and healthier, because of an ability of nanosensors to detect not only normal olfates, but also some VOCs produced by us, when we are sick even, when we have cancer. This types of smell nanosensors are that sensible, that can detect if the food we eat is fresh. That is why, the production of new super sensible nanosensors is that important.
2. Introduction The word sense comes from Latin word ‘sensus’, which directly means ‘sense’ or ‘to sense something’. Humans can be proud of having 5 senses: sight, hearing, taste, smell and touch. This senses give us the ability to receive signals from the environment and react or respond to them. Thanks this abilities we can define the sensor as a device that receives and responds to signals and stimuli from the environment. All human sensors can be divided in two groups, depending of the type of stimuli. Sight, hearing and touch have physical stimuli, like light in form of electro-magnetic waves, acoustic waves and pressure. Smell and taste respond to chemical stimuli, like odour or taste molecules [Buenger et al., 2012]. The construction tract of human and canine senses are similar and their structure can be interpreted as follows: the electro-magnetic wave hits a receptor cell in retina, a chemical reaction is trigged and then transduced, in form of an electrical signal, to the brain. So, the receptor part of the sensor senses a chemical or physical stimulus and transforms it into a form of energy. The transducer part is than capable of transducing this energy into a useful analytical signal which can be processed and displayed. Above is presents scheme of sensor structure [Buenger et al., 2012].
Creation of an ‘electronic artificial nose’, a nanosensor, which can be even more sensible than the human smell sense could have a lot of possible applications in everyday life of all of us. Construction of a gas nanosensor which could be as sensitive as dog’s nose could be useful in our life. So, in this project we have concentrated in this sensor and its potential applications.
3
3. Smell nanosensors – literature review The concept of an artificial nose comes from simulating the human olfactory system to detect different volatile compounds. Single olfactory neuron responds to several different odours while a pattern recognition process produced by multiple olfactory neurons identifies and classifies odours. Electronic noses are similar and are based on analysis using a semi-selective electronic sensor array, resulting in recognition of volatile odour patterns [Oh et al., 2011].
Bioelectronic noses use biological olfactory receptors as recognition elements, together with sensor devices, which produce and amplify electrical signals from the biological interaction of odours with receptors, as sensor elements [Lee et al., 2009]. The bioelectronic nose is expected to resemble the artificial nose, which mimics the human olfactory system more closely. Fabrication of nanosensor platform and development of a gas sensor device, would allow bioelectronic noses to be successfully used in lot of applications, like disease diagnosis, detection of bacterial infection, food freshness control, VOCs (Volatile Organic Compounds) detection. The electronic nose system is normally designed for detection and discrimination of volatile analytes with partial selectivity or proper pattern recognition. There are a lot of different types of nanosensors used in production of electronic nose. During nanotechnology development various types of nanosensors have been constructed. The most common ideas were concentrated in construction of metal oxide semiconductors (MOS), conducting polymer-based sensors, piezoelectric and optical sensor platforms [Oh et al. 2009]. Conducting polymers are widely used as sensor elements in electronic noses due to their ability to adjust their conductivity in response to organic compounds. They have a broad specificity that overlaps with that of organic vapors and display rapid and reversible physicochemical properties at ambient temperature [Turner and Magan, 2004]. The converse piezoelectric effect, which is the basis of the piezoelectric sensor, is a phenomenon in which electrical potential generates mechanical stress within the crystal.
4
Piezoelectric crystals have a ratio frequency resonance under such electric potential and are highly sensitive to the mass change applied to the crystals. Sensor using polymer-coated crystals, therefore, can detect volatile molecules adsorbed on the surface by measuring the frequency change upon mass increase [Si et al., 2007]. Optical sensors have been widely used as chemical sensors in many areas as their output signal can be precisely measured and defined. Optical sensors are more complicated than other sensors. They provide various measuring possibilities. The light source of these sensors excites volatile molecules, generating a signal that can be measured via absorbance, reflectance, fluorescence, refractive index, colorimetry or chemiluminescence. Such output signals are detected using various detectors, including photodiodes, CCD and CMOS cameras [Oh et al., 2011].
4. Overall design of new theoretical smell nanosensor Metal oxide semiconductors are one of the most common sensor systems to detect gaseous molecules. The oxide material-coated sensors interact with volatile molecules and alter the conductivity of the oxide. When oxides are exposed to VOCs, are involved in a redox reactions on the surface of the sensor or act as oxidizing agents, by which cause the shift in the resistance of the semiconductor. This kind of nanosensor system is comprised of oxidizing and reducing steps. Oxygen adsorbed from the air traps free electrons from the conduction band of the semiconductor and builds up the potential barrier on the surface. The chemical reaction that results from adsorbed O2 reacting with VOCs decreases the density of O2 on the surface and by this electrons are trapped. The change in resistance depends on the VOC interacting with the adsorbed O2 on the semiconductor as well as the metal oxide [Oh et al., 2011]. There are a lot of types the metal oxide semiconductors, which can be used as nanosensors. The most famous are sensors made by SnO2, ZnO, TiO2, WO3 and Fe2O3, because of their outstanding physical, chemical and biological properties. Sensor made by SnO2, which has a wide band-gap of 3,6eV and 300 K, is a great promising material for gas sensors, photocatalysts, dye-sensitized solar cells and lithium-ion batteries [Wang et al., 2015]. The gas sensing properties of SnO2 strongly depend on its morphology and shape. Creation of nanosensors made from SnO2 in 3D hierarchical nanostructure, constructed by well-defined 1D SnO2 nanorod units presents great activity. This type of sensor shows excellent gas sensing performance in terms of high response, reproducibility, short response/recovery times and supervisor selectivity to VOCs.
5
Our sensor made from SnO2 created from nanorod units, could form 3D structures, which allows to detect gases could be combined with human cells. The mammalian olfactory system is combined from 2 accessories: the accessory olfactory bulb and the vomeronasal organ. The main olfactory system is composed of the olfactory mucosa and olfactory bulb. The mucosa contains the respiratory epithelium and neuroepithelium, which contains neurons that express the OR (Olfactory Receptor). All the olfactory system is presented above [Pomerantz et al., 2015].
The ORs are G protein couple receptors composed of 7 transmembrane hydrophobic domains. These receptors are the first part of series of elements that transforms a mechanical stimulus into a bioelectrical signal. This signal travels from the cilia into an olfactory nerve and then into an olfactory bulb. The olfactory bulb is the only way station that allows the signal to travel from the peripheral olfactory apparatus to the brain [Quignon et al., 2012]. Substituting the natural Cilia of Receptor Cells by SnO2 nanosensor we could connect the supersensible sensor with mammalian brain, and thanks to it we could make an electric nose, which is much more sensible than our natural olfactory system. The implementation of the metal oxide nanosensor as a mammalian cell olfactory system receptor is our new theoretical potential smell nanosensor.
5. Possible fabrication of new smell nanosensors The possible fabrication of this new type of metal oxide semiconductor substituting the human olfactory receptors could be as follow. In the solution we could mix ions of Sn4+ with OH- ions of the basic solution. By this a lot of Sn(OH)4 is generated, which precipitates rapidly. In this basic environment, the [Sn(OH)6]2- complex ions are produced and during the time, by the decomposition, the SnO2 nanocrystals are creating. Then by aggregation into SnO2 nanoparticles the semiconductor is growing to create the final form of 3D hierarchical SnO2 nanostructure [Wnag et al., 2015]. Then the last step could be to implant this nanosensors into
6
cilia of receptor cells cultivated in vitro by injecting it directly in the needle suspension. Then by growing of cells, it could create some kind of connection between the sensor and cells, which in the final step could be implanted to the human olfactory system. The theoretical scheme of the fabrication of this sensor is presented above.
6. Possible applications of new generation smell nanosensors The applications of gas sensors has been extensively studied during the past decades. The most attractive character of gas sensors is that they response to a wide range of VOCs (Volatile Organic Compounds) at ambient temperature. The sensors construction allows them to recognize diverse chemical structures and various response mechanisms upon exposure to different gases, for example that from breath which has strong correlation with some diseases [Liu et al., 2012]. Thanks to it, this nanosensor can be used as a food freshness detector. This kind of machine is now used in fish freshness detection [Tang et al., 2006]. Other possible application is usage of bioelectronics nose (designed from olfactory nanosensors) that mimicked the signal pathways of human olfactory systems and thus recognized specific odorant with a high sensitivity and a human-like selectivity [Jin et al., 2012]. This kind of nanosensor can help us to detect a wide range of targets including metal ions, volatile agents, flavours, hormones and biomarkers [Lee et al., 2012]. One of the most interesting applications of this nanosensor could be diseases diagnosis, food quality inspection and spacecraft atmospheric monitoring [Hu et al., 2013]. But the most important possible application of this nanosensor could be diagnosis of the cancers (e.g. lung, breast, colorectal., prostate), by measuring the volatiles/gases that emanate from human biological media in order
7
to find distinct bio-markers indicating a disease state. In cancerous cells, a change in the rate of oxidative stress, lipid peroxidation and gene sequences leads to abnormalities in the biochemical pathways of these cells and thus to the production of specific VOCs [Pomerantz et al., 2015]. So, the importance of this nanosensor could be early stage cancer-diseases detection [Westenbrink et al., 2015]. The other possible application of usage of this nanosensor can be drug detection – like dogs can do it. Thanks to it, the drug transfer routes detection could be protected more effectively.
7. Conclusions Fabrication of new types of nanosensors is controlled and very good studied, till the phase of implementation of them into human body. If this step could be controlled as good as previous phases of (chemical or physical) production of this nanosensors we could create a great and super sensible sense in human body, which could allow us to live better. By this, we could have the opportunity to live heathier, because of permanent freshness control of food we eat. This sensor inside us could allow us to detect if we are sick in the really early stage of the disease. I hope that in the short future we will be able to live in the world with these nanosensors working in our bodies.
8. References Buenger D., Topus F., Groll J. (2012) Hydrogels in sensing applications. Progress in Polymer Science 37:1678-1719 Hu Y., Lee H., Kim S., Yun M. (2013) A highly selective chemical sensor array based on nanowire/nanostructure for gas identification. Sensors and Actuators B 181:424-431 Jin H. J., Lee S. H., Kim T. H., Park J., Song H. S., Park T. H., Hong S. (2012) Nanovescilebased bioelectronic nose platform mimicking human olfactory signal transduction. Biosensors and Bioelectronics 35:335-341 Lee S., Jun S., Ko H., Kim S., Park T. (2009) Cell-based olfactory biosensor using microfabricated planar electrode. Biosensors and Bioelectronics 24:2659-2664 Lee S. H., Kwon O. S., Song H. S., Park S. J., Sung J. H., Jang J., Park T. H. (2012) Mimicking the human smell sensing mechanism with an artificial nose platform. Biomaterials 33:17221729 Liu C., Hayashi K., Toko K. (2012) Au nanoparticles decorated polyaniline nanofiber sensor for detecting volatile sulphur compounds in expired breath. Sensors and Actuators B 161:504509 Oh E. H., Song H. S., Park T. H. (2011) Recent advances in electronic and bioelectronics noses and their biomedical applications. Enzyme and Microbial Technology 48:427-437
8
Pomerantz A., Blachman-Braun R., Galnares-Olalde J., Berebichez-Fridman R., CapursoGarcis M. (2015) The possibility of inventing new technologies in the detection of cances by applying elements of the canine olfactory apparatus. Medical Hypotheses in press. Si P., Mortensen J., Komolov A., Denborg J., Moller P. (2007) Polymer coated quartz crystal microblance sensors for detection of volatile organic compounds in gas mixtures. Analytical Chemistry Acta 597:223-230 Tang H., Yan X., Zhang H., Wang M., Yang D. (2006) Gas sensing behaviour of polyvinylpirrolidone-modified ZnO nanoparticles for trimethylamine. Sensors and Actuators B 113:324-328 Turner A., Magan N. Electronic noses and disease diagnostics. National Review of Microbiology 2:161-166 Quignon P., Rimbault M., Robin S., Galibert F. (2012) Genetics of canine olfaction and receptor diversity. Mammalian Genome 23:132-143 Wang S., Yang J., Zhang H., Wang Y., Gao X., Wang L., Zhu Z. (2015) One-spot synthesis of 3D hierarchical SnO2 nanostructures and their application for gas sensor. Sensors and Actuators B 207:83-89 Westenbrink E., Arasaradnam R., O’Connell N., Bailey C., Nwokolo C., Bardhan K., Covington J. (2015) Development and application od a new electronic nose instrument for the detection of colorectal cancer. Biosensors and Biolectronics 67:733-738
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Students:
Sabina Wilkanowicz Sankaranarayanan L. Marco Antonio Balbino
Course instructor:
Prof. Hossam Haick
Nanotechnology and Nanosensors by Coursera and TECHNION, Israel Institute of Technology 2015
Actually, I am a Project Leader at Bioinicia S.L., where I’m responsible for projects related to encapsulation of sensitive bioactive compounds using electro-hydrodynamic processing. I have a PhD in Chemical Sciences in the field of Biotechnology. My PhD research conducted at the Department of Microbiology, Gdansk University of Technology, Poland, was associated with the analysis of biofilm formation by uropathogenic E. coli strains. During PhD studies I had worked at Microbial Ecology, Nutrition and Health Department and Novel Materials and Nanotechnology Department at IATA-CSIC (Spain), where I started to work in a new research line related to influence of probiotics on human health and encapsulation of probiotics by electro-hydrodynamic processing. After my PhD thesis I also worked at EURx Molecular Biology Products (Poland) as a R&D Project Leader, where I was responsible for cloning, overexpressing and purification of new recombinant enzymes (restriction enzymes, polymerases, reverse transcriptase) and creation of new kits to purification of DNA and RNA, used in molecular biology. I have more than 10 years of experience and practical knowledge about chemical engineering, molecular biology, genetics, chemistry and microbiology.
Table of contents: 1. ABSTRACT ............................................................................................................................... 3 2. INTRODUCTION ...................................................................................................................... 3 3. SMELL NANOSENSORS – LITERATURE REVIEW ............................................................. 4 4. OVERALL DESIGN OF NEW THEORETICAL SMELL NANOSENSOR ............................ 5 6. POSSIBLE APPLICATIONS OF NEW GENERATION SMELL NANOSENSORS ............... 7 7. CONCLUSIONS ........................................................................................................................ 8 8. REFERENCES ........................................................................................................................... 8
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1. Abstract New technologies allow us to create new, better sensors, which can help people with disabilities sense or feel as healthy ones. Nanotechnology and nanosensors can be a great opportunity for us in the future to live better and easier. Creation of new electronic olfactory nanosensors can allow people to smell as sensible as other mammalians, like dogs for example. This great idea can help us to live easier and healthier, because of an ability of nanosensors to detect not only normal olfates, but also some VOCs produced by us, when we are sick even, when we have cancer. This types of smell nanosensors are that sensible, that can detect if the food we eat is fresh. That is why, the production of new super sensible nanosensors is that important.
2. Introduction The word sense comes from Latin word ‘sensus’, which directly means ‘sense’ or ‘to sense something’. Humans can be proud of having 5 senses: sight, hearing, taste, smell and touch. This senses give us the ability to receive signals from the environment and react or respond to them. Thanks this abilities we can define the sensor as a device that receives and responds to signals and stimuli from the environment. All human sensors can be divided in two groups, depending of the type of stimuli. Sight, hearing and touch have physical stimuli, like light in form of electro-magnetic waves, acoustic waves and pressure. Smell and taste respond to chemical stimuli, like odour or taste molecules [Buenger et al., 2012]. The construction tract of human and canine senses are similar and their structure can be interpreted as follows: the electro-magnetic wave hits a receptor cell in retina, a chemical reaction is trigged and then transduced, in form of an electrical signal, to the brain. So, the receptor part of the sensor senses a chemical or physical stimulus and transforms it into a form of energy. The transducer part is than capable of transducing this energy into a useful analytical signal which can be processed and displayed. Above is presents scheme of sensor structure [Buenger et al., 2012].
Creation of an ‘electronic artificial nose’, a nanosensor, which can be even more sensible than the human smell sense could have a lot of possible applications in everyday life of all of us. Construction of a gas nanosensor which could be as sensitive as dog’s nose could be useful in our life. So, in this project we have concentrated in this sensor and its potential applications.
3
3. Smell nanosensors – literature review The concept of an artificial nose comes from simulating the human olfactory system to detect different volatile compounds. Single olfactory neuron responds to several different odours while a pattern recognition process produced by multiple olfactory neurons identifies and classifies odours. Electronic noses are similar and are based on analysis using a semi-selective electronic sensor array, resulting in recognition of volatile odour patterns [Oh et al., 2011].
Bioelectronic noses use biological olfactory receptors as recognition elements, together with sensor devices, which produce and amplify electrical signals from the biological interaction of odours with receptors, as sensor elements [Lee et al., 2009]. The bioelectronic nose is expected to resemble the artificial nose, which mimics the human olfactory system more closely. Fabrication of nanosensor platform and development of a gas sensor device, would allow bioelectronic noses to be successfully used in lot of applications, like disease diagnosis, detection of bacterial infection, food freshness control, VOCs (Volatile Organic Compounds) detection. The electronic nose system is normally designed for detection and discrimination of volatile analytes with partial selectivity or proper pattern recognition. There are a lot of different types of nanosensors used in production of electronic nose. During nanotechnology development various types of nanosensors have been constructed. The most common ideas were concentrated in construction of metal oxide semiconductors (MOS), conducting polymer-based sensors, piezoelectric and optical sensor platforms [Oh et al. 2009]. Conducting polymers are widely used as sensor elements in electronic noses due to their ability to adjust their conductivity in response to organic compounds. They have a broad specificity that overlaps with that of organic vapors and display rapid and reversible physicochemical properties at ambient temperature [Turner and Magan, 2004]. The converse piezoelectric effect, which is the basis of the piezoelectric sensor, is a phenomenon in which electrical potential generates mechanical stress within the crystal.
4
Piezoelectric crystals have a ratio frequency resonance under such electric potential and are highly sensitive to the mass change applied to the crystals. Sensor using polymer-coated crystals, therefore, can detect volatile molecules adsorbed on the surface by measuring the frequency change upon mass increase [Si et al., 2007]. Optical sensors have been widely used as chemical sensors in many areas as their output signal can be precisely measured and defined. Optical sensors are more complicated than other sensors. They provide various measuring possibilities. The light source of these sensors excites volatile molecules, generating a signal that can be measured via absorbance, reflectance, fluorescence, refractive index, colorimetry or chemiluminescence. Such output signals are detected using various detectors, including photodiodes, CCD and CMOS cameras [Oh et al., 2011].
4. Overall design of new theoretical smell nanosensor Metal oxide semiconductors are one of the most common sensor systems to detect gaseous molecules. The oxide material-coated sensors interact with volatile molecules and alter the conductivity of the oxide. When oxides are exposed to VOCs, are involved in a redox reactions on the surface of the sensor or act as oxidizing agents, by which cause the shift in the resistance of the semiconductor. This kind of nanosensor system is comprised of oxidizing and reducing steps. Oxygen adsorbed from the air traps free electrons from the conduction band of the semiconductor and builds up the potential barrier on the surface. The chemical reaction that results from adsorbed O2 reacting with VOCs decreases the density of O2 on the surface and by this electrons are trapped. The change in resistance depends on the VOC interacting with the adsorbed O2 on the semiconductor as well as the metal oxide [Oh et al., 2011]. There are a lot of types the metal oxide semiconductors, which can be used as nanosensors. The most famous are sensors made by SnO2, ZnO, TiO2, WO3 and Fe2O3, because of their outstanding physical, chemical and biological properties. Sensor made by SnO2, which has a wide band-gap of 3,6eV and 300 K, is a great promising material for gas sensors, photocatalysts, dye-sensitized solar cells and lithium-ion batteries [Wang et al., 2015]. The gas sensing properties of SnO2 strongly depend on its morphology and shape. Creation of nanosensors made from SnO2 in 3D hierarchical nanostructure, constructed by well-defined 1D SnO2 nanorod units presents great activity. This type of sensor shows excellent gas sensing performance in terms of high response, reproducibility, short response/recovery times and supervisor selectivity to VOCs.
5
Our sensor made from SnO2 created from nanorod units, could form 3D structures, which allows to detect gases could be combined with human cells. The mammalian olfactory system is combined from 2 accessories: the accessory olfactory bulb and the vomeronasal organ. The main olfactory system is composed of the olfactory mucosa and olfactory bulb. The mucosa contains the respiratory epithelium and neuroepithelium, which contains neurons that express the OR (Olfactory Receptor). All the olfactory system is presented above [Pomerantz et al., 2015].
The ORs are G protein couple receptors composed of 7 transmembrane hydrophobic domains. These receptors are the first part of series of elements that transforms a mechanical stimulus into a bioelectrical signal. This signal travels from the cilia into an olfactory nerve and then into an olfactory bulb. The olfactory bulb is the only way station that allows the signal to travel from the peripheral olfactory apparatus to the brain [Quignon et al., 2012]. Substituting the natural Cilia of Receptor Cells by SnO2 nanosensor we could connect the supersensible sensor with mammalian brain, and thanks to it we could make an electric nose, which is much more sensible than our natural olfactory system. The implementation of the metal oxide nanosensor as a mammalian cell olfactory system receptor is our new theoretical potential smell nanosensor.
5. Possible fabrication of new smell nanosensors The possible fabrication of this new type of metal oxide semiconductor substituting the human olfactory receptors could be as follow. In the solution we could mix ions of Sn4+ with OH- ions of the basic solution. By this a lot of Sn(OH)4 is generated, which precipitates rapidly. In this basic environment, the [Sn(OH)6]2- complex ions are produced and during the time, by the decomposition, the SnO2 nanocrystals are creating. Then by aggregation into SnO2 nanoparticles the semiconductor is growing to create the final form of 3D hierarchical SnO2 nanostructure [Wnag et al., 2015]. Then the last step could be to implant this nanosensors into
6
cilia of receptor cells cultivated in vitro by injecting it directly in the needle suspension. Then by growing of cells, it could create some kind of connection between the sensor and cells, which in the final step could be implanted to the human olfactory system. The theoretical scheme of the fabrication of this sensor is presented above.
6. Possible applications of new generation smell nanosensors The applications of gas sensors has been extensively studied during the past decades. The most attractive character of gas sensors is that they response to a wide range of VOCs (Volatile Organic Compounds) at ambient temperature. The sensors construction allows them to recognize diverse chemical structures and various response mechanisms upon exposure to different gases, for example that from breath which has strong correlation with some diseases [Liu et al., 2012]. Thanks to it, this nanosensor can be used as a food freshness detector. This kind of machine is now used in fish freshness detection [Tang et al., 2006]. Other possible application is usage of bioelectronics nose (designed from olfactory nanosensors) that mimicked the signal pathways of human olfactory systems and thus recognized specific odorant with a high sensitivity and a human-like selectivity [Jin et al., 2012]. This kind of nanosensor can help us to detect a wide range of targets including metal ions, volatile agents, flavours, hormones and biomarkers [Lee et al., 2012]. One of the most interesting applications of this nanosensor could be diseases diagnosis, food quality inspection and spacecraft atmospheric monitoring [Hu et al., 2013]. But the most important possible application of this nanosensor could be diagnosis of the cancers (e.g. lung, breast, colorectal., prostate), by measuring the volatiles/gases that emanate from human biological media in order
7
to find distinct bio-markers indicating a disease state. In cancerous cells, a change in the rate of oxidative stress, lipid peroxidation and gene sequences leads to abnormalities in the biochemical pathways of these cells and thus to the production of specific VOCs [Pomerantz et al., 2015]. So, the importance of this nanosensor could be early stage cancer-diseases detection [Westenbrink et al., 2015]. The other possible application of usage of this nanosensor can be drug detection – like dogs can do it. Thanks to it, the drug transfer routes detection could be protected more effectively.
7. Conclusions Fabrication of new types of nanosensors is controlled and very good studied, till the phase of implementation of them into human body. If this step could be controlled as good as previous phases of (chemical or physical) production of this nanosensors we could create a great and super sensible sense in human body, which could allow us to live better. By this, we could have the opportunity to live heathier, because of permanent freshness control of food we eat. This sensor inside us could allow us to detect if we are sick in the really early stage of the disease. I hope that in the short future we will be able to live in the world with these nanosensors working in our bodies.
8. References Buenger D., Topus F., Groll J. (2012) Hydrogels in sensing applications. Progress in Polymer Science 37:1678-1719 Hu Y., Lee H., Kim S., Yun M. (2013) A highly selective chemical sensor array based on nanowire/nanostructure for gas identification. Sensors and Actuators B 181:424-431 Jin H. J., Lee S. H., Kim T. H., Park J., Song H. S., Park T. H., Hong S. (2012) Nanovescilebased bioelectronic nose platform mimicking human olfactory signal transduction. Biosensors and Bioelectronics 35:335-341 Lee S., Jun S., Ko H., Kim S., Park T. (2009) Cell-based olfactory biosensor using microfabricated planar electrode. Biosensors and Bioelectronics 24:2659-2664 Lee S. H., Kwon O. S., Song H. S., Park S. J., Sung J. H., Jang J., Park T. H. (2012) Mimicking the human smell sensing mechanism with an artificial nose platform. Biomaterials 33:17221729 Liu C., Hayashi K., Toko K. (2012) Au nanoparticles decorated polyaniline nanofiber sensor for detecting volatile sulphur compounds in expired breath. Sensors and Actuators B 161:504509 Oh E. H., Song H. S., Park T. H. (2011) Recent advances in electronic and bioelectronics noses and their biomedical applications. Enzyme and Microbial Technology 48:427-437
8
Pomerantz A., Blachman-Braun R., Galnares-Olalde J., Berebichez-Fridman R., CapursoGarcis M. (2015) The possibility of inventing new technologies in the detection of cances by applying elements of the canine olfactory apparatus. Medical Hypotheses in press. Si P., Mortensen J., Komolov A., Denborg J., Moller P. (2007) Polymer coated quartz crystal microblance sensors for detection of volatile organic compounds in gas mixtures. Analytical Chemistry Acta 597:223-230 Tang H., Yan X., Zhang H., Wang M., Yang D. (2006) Gas sensing behaviour of polyvinylpirrolidone-modified ZnO nanoparticles for trimethylamine. Sensors and Actuators B 113:324-328 Turner A., Magan N. Electronic noses and disease diagnostics. National Review of Microbiology 2:161-166 Quignon P., Rimbault M., Robin S., Galibert F. (2012) Genetics of canine olfaction and receptor diversity. Mammalian Genome 23:132-143 Wang S., Yang J., Zhang H., Wang Y., Gao X., Wang L., Zhu Z. (2015) One-spot synthesis of 3D hierarchical SnO2 nanostructures and their application for gas sensor. Sensors and Actuators B 207:83-89 Westenbrink E., Arasaradnam R., O’Connell N., Bailey C., Nwokolo C., Bardhan K., Covington J. (2015) Development and application od a new electronic nose instrument for the detection of colorectal cancer. Biosensors and Biolectronics 67:733-738
9
